If you are approaching menopause and you have some extra belly fat, new research suggests you might want to shed some inches now.
Women who carry weight around their midsection during menopause may be more likely to develop heart disease even if their overall weight remains the same, researchers report.
For every 20% increase in belly fat, the thickness of the carotid artery lining grew by 2%, according to their study. The carotid arteries carry blood to the head and neck, and carotid artery thickness is considered an early sign of heart disease.
The new findings held even after the researchers controlled for other heart disease risk factors such as weight and BMI, a measure of body fat based on height and weight.
Heart disease is the No. 1 killer of women in the United States, and it's not necessarily your weight but where it goes that affects your heart disease risk, said study author Samar El Khoudary, an associate professor of epidemiology at the University of Pittsburgh Graduate School of Public Health.
Exactly what makes belly fat so dangerous is not fully understood yet. But "it has been shown that this fat is metabolically active and can secrete inflammatory markers that may raise risk for heart disease," she explained.
The researchers measured fat surrounding the abdominal organs (visceral fat) with CT scans and the thickness of the internal carotid artery lining using ultrasounds in about 360 women from Pittsburgh and Chicago who participated in the Study of Women's Health Across the Nation (SWAN) Heart study. Women in the study were about 51, which is the average age for entering menopause in the United States.
In addition to increases in carotid artery thickness associated with belly fat, the investigators found that visceral belly fat goes up with aging and that the rate of increase picks up at the time of the menopause.
Importantly, these changes may not be reflected by your weight or BMI, El Khoudary said.
"Two women can have the same BMI, but if one stores her weight in her abdomen and the other in her thighs, the woman who stores fat in her abdomen is at higher risk for heart disease, and that would be missed if we just focused on BMI," she said.
You don't need pricey CT imaging scans to measure belly fat either, El Khoudary said. Regularly tracking waist circumference with measuring tape can pick up increases in abdominal fat.
"Women need to be careful and monitor where fat storage changes occur as they transition to menopause," she noted. It's also important that women with more belly fat control other risk factors for heart disease such as high cholesterol, high blood pressure and insulin resistance, a precursor to diabetes, El Khoudary said.
More research is needed to see if certain diet, exercise or other lifestyle changes can reduce belly fat and carotid artery thickness as well as whether there is a clear cutoff point where waist circumference becomes a threat, El Khoudary said.
The study was published March 3 in the journal Menopause.
The findings should serve as a wake-up call for women approaching menopause, said Mercedes Carnethon, vice chair of preventive medicine at Northwestern University Feinberg School of Medicine in Chicago.
"It is important for women to know that their body composition is shifting with aging and that these changes start two years before menopause and continue with aging," said Carnethon, who was not involved in the new study.
"Maintaining a healthy lifestyle and balanced diet to prevent overall weight gain may be one strategy to prevent these aging-associated shifts in body composition that can increase the risk of having a heart attack," she said.